Reversible Beta-Hydrogen Elimination of Three-Coordinate Iron(II) Alkyl Complexes: Mechanistic and Thermodynamic Studies

Description:

Article discussing mechanistic and thermodynamic studies and reversible beta-hydrogen elimination of three-coordinate iron(II) alkyl complexes.

Creator(s):
Creation Date: October 1, 2004
Partner(s):
UNT College of Arts and Sciences
Collection(s):
UNT Scholarly Works
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Total Uses: 369
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Creator (Author):
Vela, Javier

University of Rochester

Creator (Author):
Vaddadi, Sridhar

University of North Texas

Creator (Author):
Cundari, Thomas R., 1964-

University of North Texas

Creator (Author):
Smith, Jeremy M.

University of Rochester; New Mexico State University

Creator (Author):
Gregory, Elizabeth A.

University of Rochester

Creator (Author):
Lachicotte, Rene J.

University of Rochester

Creator (Author):
Flaschenriem, Christine J.

University of Rochester

Creator (Author):
Holland, Patrick L.

University of Rochester

Publisher Info:
Publisher Name: American Chemical Society
Place of Publication: [Washington, D.C.]
Date(s):
  • Creation: October 1, 2004
Description:

Article discussing mechanistic and thermodynamic studies and reversible beta-hydrogen elimination of three-coordinate iron(II) alkyl complexes.

Degree:
Department: Chemistry
Note:

Reprinted with permission from Organometallics. Copyright 2004 American Chemical Society.

Note:

Abstract: High-spin organometallic complexes have not received extensive mechanistic study, despite their potential importance as unsaturated intermediates in catalytic transformations. The authors have found that, with a suitably bulky bidentate ligand, three-coordinate, high-spin alkyl complexes of iron(II) are stable. They undergo isomerization and exchange reactions of the alkyl group through β-hydride elimination and reinsertion, and the β-hydride elimination step is rate-limiting. The alkyl complexes transfer a β-hydrogen atom to C=C, C=N, and C=O double bonds and undergo deprotonation by Brønsted acids. The reversible β-hydride elimination reactions can be used to explore relative M-C bond energies. Competition experiments and density functional calculations demonstrate an enthalpic preference for alkyl isomers with iron bound to the terminal carbon of the alkyl fragment. This preference arises from steric and electronic effects. The steric preference could be overcome with a phenyl substituent, which steers iron to the benzylic position. A Hammett correlation and density functional calculations suggest that the substituent effect is attributable to resonance stabilization of partial negative charge on the alkyl ligand.

Physical Description:

14 p.

Language(s):
Subject(s):
Keyword(s): beta-hydrogen | three-coordinate iron(II) | alkyl complexes | mechanistic | thermodynamics
Source: Organometallics, 2004, Washington DC: American Chemical Society, pp. 5226-5239
Partner:
UNT College of Arts and Sciences
Collection:
UNT Scholarly Works
Identifier:
  • DOI: 10.1021/om049415+
  • ARK: ark:/67531/metadc77181
Resource Type: Article
Format: Text
Rights:
Access: Public
Citation:
Publication Title: Organometallics
Volume: 23
Page Start: 5226
Page End: 5239
Peer Reviewed: Yes